I have read on numerous forums about fuel guages not working. 86 f-150 swb 4x4 302 efi. dropped my rear tank today cleaned everything including the ring that lock's down the new sending unit to the tank. Thought i had a grounding problem. The guage climbs as the tank get's empty and reads e when full? any ideas

 

Any chance that the polarity on the sending unit is reversed? Other than that, it sounds like you needs a new one... Uh Oh, I should have read closer, you already have a new one, sorry

 

I agree on the polarity. You must have the wires reversed.

 

It is impossible to reverse the polarity on mine since the 4 wires that go to the tank are encased in a plastic housing and only fit on one way. I thought the wires were reversed myself and tried to hook it up 180 degrees from where it was the harness would not fit. any other suggestions?

 

Maybe you got a bad sending unit. It happens.

 

E is now enough and F is fill me.